230 Trans. Acad. Sci. of St. Louis 
be justly regarded as doing as much damage to the law- 
ful inhabitants as either the Chrysits or the Chalcids. 
The Diptera, however, came later in the season, and 
possibly sought different victims. Dipterous parasites 
were first seen on July 30, 1917—a half-dozen represent- 
ing two or three species. As days went by, they became 
more numerous in species and numbers. The details be- 
low relate their activities. 
Copecrypta ruficauda Coq. [C. H. T. Townsend]. This 
fly was seen to rest for several minutes on the clay 
bank on August 10. While I was wondering how I 
could capture it, it flew to my wrist and became so in- 
tent on drinking the perspiration that I picked it up 
easily in my hand. It was the only specimen seen there. 
Archytas aterrima R. D. [C. H. T. Townsend]. This 
fly belonging to the family Tachinidae, and commonly 
called the tachina fly, is parasitic on other insects. One 
specimen was taken at the bank on July 31. Like Cope- 
crypta ruficauda, this fly was taken when it flew to my 
hand to drink the perspiration. 
Sarcomacronychia trivittata T. [C. H. T. Townsend]. 
The first time this fly was seen at the bank was 
September 6, when two specimens were taken. They 
spent their time flying about the bank, often resting 
upon it and seldom going far away from it; this con- 
duct indicated that there must be some attraction there. 
A third individual was observed on October 3, 1917. 
Parametopia sp. [C. H. T. Townsend]. One such pest 
was seen to follow the wasp, Ancistrocerus fulvipes, 
as she entered her nest laden with a caterpillar on Sep- 
tember 12. A second individual was scen to follow the 
same species of wasp on October 3, 1917, as she was 8% 
ing to the nest. This does not mean that this fly has 
